AWS is going to begin charging extra for routable IPv4 addresses soon.
There's really no point in having a relay in the cloud anymore anyway,
since a) all outbound messages are sent via the local relay and b) no
messages are sent to anyone except me.
The value of the `shlib_directory` is dependent the system architecture.
Specifically, x86_64 machines use `/usr/lib64/postfix`, while everything
else uses `/usr/lib/postfix`. This role was originally deployed on a
Raspberry Pi, so the original path was correct. Attempting to deploy it
on an x86_64 machine revealed the error.
This commit adds a new task that loads a variables file based on the
architecture. Each option defines an `arch_libdir` variable, which can
be expanded in the `postfix_shlib_directory` variable as needed.
The *postfix* role installs and configures the Postfix MTA. It currently
supports a number of modes, including direct transfer and relay. Relay
mode supports STARTTLS security and PLAIN authentication.
Dustin